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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package java.awt.event;

import java.awt.Adjustable;

import java.awt.AWTEvent;

import java.lang.annotation.Native;

/**

 * The adjustment event emitted by Adjustable objects like

 * {@link java.awt.Scrollbar} and {@link java.awt.ScrollPane}.

 * When the user changes the value of the scrolling component,

 * it receives an instance of {@code AdjustmentEvent}.

 * <p>

 * An unspecified behavior will be caused if the {@code id} parameter

 * of any particular {@code AdjustmentEvent} instance is not

 * in the range from {@code ADJUSTMENT_FIRST} to {@code ADJUSTMENT_LAST}.

 * <p>

 * The {@code type} of any {@code AdjustmentEvent} instance takes one of the following

 * values:

 *                     <ul>

 *                     <li> {@code UNIT_INCREMENT}

 *                     <li> {@code UNIT_DECREMENT}

 *                     <li> {@code BLOCK_INCREMENT}

 *                     <li> {@code BLOCK_DECREMENT}

 *                     <li> {@code TRACK}

 *                     </ul>

 * Assigning the value different from listed above will cause an unspecified behavior.

 * @see java.awt.Adjustable

 * @see AdjustmentListener

 *

 * @author Amy Fowler

 * @since 1.1

 */

public class AdjustmentEvent extends AWTEvent {

    /**

     * Marks the first integer id for the range of adjustment event ids.

     */

    public static final int ADJUSTMENT_FIRST    = 601;

    /**

     * Marks the last integer id for the range of adjustment event ids.

     */

    public static final int ADJUSTMENT_LAST     = 601;

    /**

     * The adjustment value changed event.

     */

    public static final int ADJUSTMENT_VALUE_CHANGED = ADJUSTMENT_FIRST; //Event.SCROLL_LINE_UP

    /**

     * The unit increment adjustment type.

     */

    @Native public static final int UNIT_INCREMENT      = 1;

    /**

     * The unit decrement adjustment type.

     */

    @Native public static final int UNIT_DECREMENT      = 2;

    /**

     * The block decrement adjustment type.

     */

    @Native public static final int BLOCK_DECREMENT     = 3;

    /**

     * The block increment adjustment type.

     */

    @Native public static final int BLOCK_INCREMENT     = 4;

    /**

     * The absolute tracking adjustment type.

     */

    @Native public static final int TRACK               = 5;

    /**

     * The adjustable object that fired the event.

     *

     * @serial

     * @see #getAdjustable

     */

    Adjustable adjustable;

    /**

     * {@code value} will contain the new value of the

     * adjustable object.  This value will always be  in a

     * range associated adjustable object.

     *

     * @serial

     * @see #getValue

     */

    int value;

    /**

     * The {@code adjustmentType} describes how the adjustable

     * object value has changed.

     * This value can be increased/decreased by a block or unit amount

     * where the block is associated with page increments/decrements,

     * and a unit is associated with line increments/decrements.

     *

     * @serial

     * @see #getAdjustmentType

     */

    int adjustmentType;

    /**

     * The {@code isAdjusting} is true if the event is one

     * of the series of multiple adjustment events.

     *

     * @since 1.4

     * @serial

     * @see #getValueIsAdjusting

     */

    boolean isAdjusting;

    /*

     * JDK 1.1 serialVersionUID

     */

     private static final long serialVersionUID = 5700290645205279921L;

    /**

     * Constructs an {@code AdjustmentEvent} object with the

     * specified {@code Adjustable} source, event type,

     * adjustment type, and value.

     * <p> This method throws an

     * {@code IllegalArgumentException} if {@code source}

     * is {@code null}.

     *

     * @param source The {@code Adjustable} object where the

     *               event originated

     * @param id     An integer indicating the type of event.

     *                     For information on allowable values, see

     *                     the class description for {@link AdjustmentEvent}

     * @param type   An integer indicating the adjustment type.

     *                     For information on allowable values, see

     *                     the class description for {@link AdjustmentEvent}

     * @param value  The current value of the adjustment

     * @throws IllegalArgumentException if {@code source} is null

     * @see #getSource()

     * @see #getID()

     * @see #getAdjustmentType()

     * @see #getValue()

     */

    public AdjustmentEvent(Adjustable source, int id, int type, int value) {

        this(source, id, type, value, false);

    }

    /**

     * Constructs an {@code AdjustmentEvent} object with the

     * specified Adjustable source, event type, adjustment type, and value.

     * <p> This method throws an

     * {@code IllegalArgumentException} if {@code source}

     * is {@code null}.

     *

     * @param source The {@code Adjustable} object where the

     *               event originated

     * @param id     An integer indicating the type of event.

     *                     For information on allowable values, see

     *                     the class description for {@link AdjustmentEvent}

     * @param type   An integer indicating the adjustment type.

     *                     For information on allowable values, see

     *                     the class description for {@link AdjustmentEvent}

     * @param value  The current value of the adjustment

     * @param isAdjusting A boolean that equals {@code true} if the event is one

     *               of a series of multiple adjusting events,

     *               otherwise {@code false}

     * @throws IllegalArgumentException if {@code source} is null

     * @since 1.4

     * @see #getSource()

     * @see #getID()

     * @see #getAdjustmentType()

     * @see #getValue()

     * @see #getValueIsAdjusting()

     */

    public AdjustmentEvent(Adjustable source, int id, int type, int value, boolean isAdjusting) {

        super(source, id);

        adjustable = source;

        this.adjustmentType = type;

        this.value = value;

        this.isAdjusting = isAdjusting;

    }

    /**

     * Returns the {@code Adjustable} object where this event originated.

     *

     * @return the {@code Adjustable} object where this event originated

     */

    public Adjustable getAdjustable() {

        return adjustable;

    }

    /**

     * Returns the current value in the adjustment event.

     *

     * @return the current value in the adjustment event

     */

    public int getValue() {

        return value;

    }

    /**

     * Returns the type of adjustment which caused the value changed

     * event.  It will have one of the following values:

     * <ul>

     * <li>{@link #UNIT_INCREMENT}

     * <li>{@link #UNIT_DECREMENT}

     * <li>{@link #BLOCK_INCREMENT}

     * <li>{@link #BLOCK_DECREMENT}

     * <li>{@link #TRACK}

     * </ul>

     * @return one of the adjustment values listed above

     */

    public int getAdjustmentType() {

        return adjustmentType;

    }

    /**

     * Returns {@code true} if this is one of multiple

     * adjustment events.

     *

     * @return {@code true} if this is one of multiple

     *         adjustment events, otherwise returns {@code false}

     * @since 1.4

     */

    public boolean getValueIsAdjusting() {

        return isAdjusting;

    }

    public String paramString() {

        String typeStr;

        switch(id) {

          case ADJUSTMENT_VALUE_CHANGED:

              typeStr = "ADJUSTMENT_VALUE_CHANGED";

              break;

          default:

              typeStr = "unknown type";

        }

        String adjTypeStr;

        switch(adjustmentType) {

          case UNIT_INCREMENT:

              adjTypeStr = "UNIT_INCREMENT";

              break;

          case UNIT_DECREMENT:

              adjTypeStr = "UNIT_DECREMENT";

              break;

          case BLOCK_INCREMENT:

              adjTypeStr = "BLOCK_INCREMENT";

              break;

          case BLOCK_DECREMENT:

              adjTypeStr = "BLOCK_DECREMENT";

              break;

          case TRACK:

              adjTypeStr = "TRACK";

              break;

          default:

              adjTypeStr = "unknown type";

        }

        return typeStr

            + ",adjType="+adjTypeStr

            + ",value="+value

            + ",isAdjusting="+isAdjusting;

    }

}